1. Field
The following description relates to a Hall based on semiconductor device that is capable of improving doping profile of Well region (Deep N well) which is formed on a semiconductor substrate thereby providing identical sensing ability with conventional Hall sensor and reducing electricity consumption.
2. Description of Related Art
A Hall sensor or a Hall effect sensor is a device that detects a direction and size of a magnetic field by using the Hall effect. The Hall effect is the application of magnetic field to a conductor through which electrical current flows to generate voltage in a direction perpendicular to the electrical current and the magnetic field. The Hall sensor is used as an electronic compass, and particularly, a semiconductor-based Hall sensor, i.e., a Hall sensor implemented by a CMOS (complementary metal-oxide semiconductor) is widely used.
In a conventional Hall sensor or Hall element, a sensing region is formed on a semiconductor substrate. The sensing region is typically shaped in the form of a cross when viewed from the top, and electrodes are formed on the cross-shaped sensing region.
When a magnetic field is applied to the conventional Hall sensor, two facing electrodes among four electrodes are used to provide electric current flow, and the other two facing electrodes are used to provide Hall voltage generated in a direction perpendicular to the direction of flow of electrical current. In this way, the conventional Hall sensor senses the Hall voltage to detect the direction and size of the magnetic field.
The sensing region is an N-type doped well region (Deep N-well) on a P-type dopant doped semiconductor substrate. The well region (Deep N-well) is formed by ion injection process and a comparatively long enlargement process. The well region surface is formed to have highest doping concentration. Moreover, a semiconductor substrate can have various defects on the semiconductor surface and a relatively thin region with respect to the semiconductor surface. Additional process can be conducted to remove the various defects during manufacturing process. However, it is not easy to eliminate semiconductor substrate defects.
Accordingly, manufacturing a Hall sensor based on a semiconductor substrate with defects, leads to degradation in the Hall sensor's sensing ability. Electric current flows between the aforementioned two electrodes that face each other and are formed adjacent to the semiconductor substrate surface. Thus, electricity current flow can be disturbed due to various defects on a semiconductor substrate surface and the function of the Hall sensor can be degraded due to the occurrence of noise.
A Hall sensor detects direction and magnitude of a magnetic field by sensing Hall voltage and in order to do so Hall current should be provided. However, oversupply of Hall current to improve Hall sensor's sensing ability leads to a drain of the battery of the portable devices. A portable device with a Hall sensor should increase hours of battery use but oversupply of Hall current leads to more consumption of battery charge. Therefore, consumption current of Hall current should be minimized while providing identical sensing ability with conventional art.